public class E_4{
    public static void main(String[] args) {
        int [] a={10,20,30,40},b[]={{1,2},{4,5,6,7}};
        b[0]=a;
        b[0][1]=b[1][3];
        System.out.println(b[0][3]);//代码1
        System.out.println(a[1]);//代码2
    }
}